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Category Archives: Bottom Trawl Surveys

With a couple days left to fish, we’re closing in on the end of leg 1! It’s that point in the leg when everything begins to look familiar and routine may have taken over. But if you’re patient and keep your eyes open, you’re sure to see something. With that said, here are some highlights from the last couple of days!

We woke up to an announcement that a large pod of common dolphins were jumping and swimming straight towards the boat. There were at least 50 of them! The whole show lasted 5-10 minutes, and just like that, they were gone. It’s amazing how quickly these sightings come and go.

Video by Jennifer Casey, NOAA Fisheries

We’ve been sampling in deeper water these last couple of days, and a neat Scorpaenidae fish came up in the net. It may look similar to our black belly rosefish, Helicolenus dactylopterus, but there are some noticeable differences. This fish is a bright orange color and has one extremely long dorsal spine. When the mouth is open, you’ll see a bright yellow throat while the blackbelly rosefish’s is, as you would expect, black.

Scorpaenidae are a group of predatory marine fish that includes scoropionfishes or rockfishes, Photo credit: NOAA Fisheries/Christine Kircun

Some lobsters we catch have lost one or both of their arms. Though, it’s not a permanent state because they can be regrown, and that’s exactly what one of the lobsters we caught was doing! At first glance, it may seem like it has only one arm, but look closer, and you can see that a replacement arm has just started growing.

At another station, we caught a beautiful starfish. We are wondering if it belongs to the genus Coronaster. This animal has 11 delicate arms and is an orange-red color. After pictures were taken, some arms were detached. It seemed odd for that to happen so quickly and after minimal handling. Perhaps it could be some kind of defense mechanism. It will be brought back to the lab for further identification.

Coronaster is a species of starfish, or sea star. Photo credit: NOAA Fisheries/Christine Kircun.

A benefit of being on day watch, noon to midnight, is the chance to witness amazing sunsets. When the weather is just right, the sky can be remarkable, and it’s difficult to resist taking a moment to be still and enjoy the view.

Some day watch scientists, watching the sunset after working up a station. Left to right: Kelcie Bean, Zackery Fyke, Lacey Bluemel, and Jennifer Casey.

Despite Hurricane Florence’s destruction on the Carolina coasts, the FSV Henry B. Bigelow has kept sampling stations at a steady pace. We are currently outside Long Island, well out of the reach of the hurricane’s wind and rain. As of now, it’s all clear for us to keep sampling stations and working up fish, but fish aren’t the only thing we’re catching in nets.

The ocean is amazingly diverse. There are well known animals such as tuna, cod, and whales. They could be valued for recreational enjoyment, commercial importance or intrinsic pleasure. And there are numerous animals such as starfish, sea urchins, jellyfish, corals, and sponges that are only found in the ocean. But there are hundreds of easily overlooked, very small yet vitally important species that benefit all living creatures, aquatic and terrestrial: plankton.

Simply put, plankton are very small, sometimes microscopic animals (zooplankton) and plants (phytoplankton) that drift in the water. Found in both fresh and salt water, they are the base of the aquatic food web. Not just that, but phytoplankton produce about half of Earth’s oxygen! Because of their crucial environmental role, it is extremely important to study and monitor these fascinating organisms, and we have a protocol for doing just that on the bottom trawl surveys.

Plankton tows are cast at select stations on the FSV Henry B. Bigelow. This is called a ‘bongo’ because the two nets used look like bongos. The bongo is lowered over the sidesampling station to about 5-10m from the bottom, depending on the ground type and weather conditions. As soon as it reaches its appropriate depth, it’s brought back to the surface. This gives us a vertical profile of the organisms in that area.The nets are washed down into a sieve, and the plankton are preserved with formalin in glass jars which will be examined back on land after the survey is completed.

Before the jars are preserved, a quick, first glance may leave the observer uninterested. But simply wait a moment, and the jar comes to life! Depending on the sampling location and time of year, ostracods, copepods, protozoans, jellyfish, mysids…. can be seen moving and zooming all over. So the next time you’re enjoying the beach and gazing out on the water, know that it is far from empty! You are actually watching thousands and thousands of plankton, working hard to support life in the ocean and on land. So take a deep breath and say “Thank you!”

Plankton studies is not my area of focus, but it is for the people in the NEFSC Oceans and Climate Branch! Check out their website at Oceans and Climate Branch for more information.

We’re almost a week into leg I of the bottom trawl survey on the FSV Henry B. Bigelow, and it’s off to a great start! Despite Hurricane Florence slowly approaching from the southeast, the weather has been absolutely gorgeous. The water is flat, and the sky is full of beautiful clouds. One of them briefly produced a water spout.

Water spout forming. Photo credit: NOAA Fisheries/Christine Kircun

While off the coast of North Carolina, we saw the Diamond Shoals Lighthouse. With so many shoals along the coast of North Carolina, lighthouses were extremely important to warn sailors of the dangers below.

And of course, it’s always exciting to see what the net brings up. Most of the animals have been small, but a couple sizable specimens made it to our sampling stations. Cobia (Rachycentron canadum) is a pelagic, flatheaded fish that spends most of its time alone except when they aggregate annually to mate. Currently, efforts to domestically cultivate cobia for food are underway.

Cobia. Photo credit: NOAA Fisheries/Christine Kircun

Grey triggerfish (Balistes capriscus) is found all along the eastern US coast. These fish travel through the water with wave-like movements of their dorsal and anal fins. They communicate with grunting and hissing noises. Clicking noises are made when the teeth behind its fleshy lips are rubbed together.

A grey triggerfish. Photo credit: NOAA Fisheries/Christine Kircun

The common octopus (Octopus vulgaris) is an intelligent cephalopod that eats bivalves (mollusks with two shells) and crabs. They are known to leave the empty shells

in what’s known as midden piles right outside whatever space they’ve decided to call home. These piles are a unique way to show researchers what kind of bivalves and crabs are in the area since an octopus can more effectively comb through its habitat as it hunts for food.

While out here on the Bigelowat the southern edge of the Northeast Channel, we’ve caught some lobsters, and just in time. Sailing with us is Joe Kunkel, a former professor and now professor emeritus at UMass Amherst, who is investigating a shell disease found on some lobsters.

Map showing location of the Northeast Channel

Shell disease is an epizootic, or temporarily prevalent and widespread, disease found on lobsters. Unofficially, it’s suggested to be caused by a bacterium called Aquamarina. It’s denoted by circular lesions on the top part of the carapace. The lesions start out microscopic, but once visible, hundreds of organisms, such as other bacteria, protozoans and nematodes, can be found living in the infected area. During the 1980s, about 1 in 10,000 lobsters may have been seen with shell disease. By the late 1990s, hot spots with up to 70% of the population showing signs of lesions were seen in the Narragansett and Buzzards Bay areas.

Joe suggests that the prevalence of the disease increases as the lobsters’ vulnerability to it increases. This means the shell’s protective ability plays an important role. Minerals composing the shell include calcium, phosphate and magnesium. The chemical reactions between these minerals dissolving in the surrounding sea water create a basic (high pH), ‘unstirred layer’. Think of it as a barrier between the lobster and seawater where a lot of mineral mixing is happening. Have you ever noticed that a lobster feels a little slippery? The slippery feeling is that protective barrier.

In order to grow, lobsters molt their hard, exterior shell. Leading up to molting, a reserve of calcium carbonate and minerals in the endocuticle, or inner shell layer, are resorbed through the epidermal cell layer. A new, soft shell matrix is formed underneath the old shell. Once molted, they eat their old shell, bringing all the rest of the minerals back into their body. They use the resorbed and eaten minerals to establish their new shell. It takes about seven days for the shell to feel hard, and it’ll be several more weeks until the shell reaches its maximum hardness. But their new shell has to be bigger so they also need to consume more minerals from their diet. This time of shell establishment is the vulnerable phase when shell disease may sneak in.

If a lobster isn’t able to consume enough added minerals, the new shell could be thinner or weaker in some areas. As global warming changes the temperature and chemistry of the ocean, lobsters may find it increasingly difficult to obtain the necessary amount of minerals, added to what they already have stored, and regrow a shell to its maximum thickness and hardness as well as building reserves for its yet bigger shell next year. Possibly, those areas of mineral thinness, or shell weakness, are spots of vulnerability to shell disease. If the protective barrier isn’t as effective, the lobsters are rendered more vulnerable, giving the bacteria a chance to establish a lesion.

The mineralization is a process that spans multiple years, and the lobsters need an adequate mineral supply to achieve a healthy cuticle that is not vulnerable to infection. We are making it harder for the lobsters by feeding them low-calcium bait. We could possibly have a healthier lobster population in the face of ocean acidification if we feed them a higher calcium carbonate bait. – Joe Kunkel

But if a lobster has shell disease, not all is lost! If they are able to shed their shell, the disease goes with it, and they are safe. Unfortunately, it’s not that simple. First, younger lobsters benefit from multiple molts a year as they are growing very fast. They are rarely killed because shell disease does not have the time to develop to advanced stages. For older lobsters, molting is reduced to once a year in the summer. This means that if the lobster is vulnerable to shell disease due to a compromised shell, it may develop lesions at some point during the year. As a result, the most severe cases are expected right before molting. As long as the infection hasn’t made its way through the epidermal cell layer, the lobster has a chance to molt the shell and have a new beginning, disease free with a new shell. Otherwise, the infection enters the blood stream and kills the lobster.

Females have an added hurdle to overcome because they don’t molt while carrying eggs. Molting for these females may be delayed for up to six months! This means any lesions on the shell have six more months to reach the blood stream. Large, healthy and reproductively successful females are extremely important for sustaining a population, so it’s disconcerting to see this condition having an exaggerated effect on females.

But where there are problems, there are people seeking solutions. One idea is to supplement their diets by feeding lobsters in their traps with bait that contains more minerals needed for shell growth. Another idea is to harvest them sooner after they molt. This may decrease the amount of lobsters caught with shell disease as it hasn’t had time to establish itself. Lobsters with shell disease are usually either discarded or if abundant they are sent to the cannery. Since the lesions are only on the cuticle, the meat is perfectly fine. Lobsters with shell disease are not desirable for boiling in the shell because the lovely cherry red color is replaced with a rusted-metal look.

A unique opportunity that’s offered for teachers to participate in the NOAA surveys is the Teacher At Sea (TAS) program. It gives teachers from all 50 states, Puerto Rico, Guam and American Samoa the opportunity to participate on our surveys. This leg, we were fortunate to have Thomas Jenkins from Ohio sail with us on the Bigelowduring the spring bottom trawl survey.

With his positive attitude, creativity and excitement to learn, he was the perfect fit! Aside from teaching 8th grade engineering and general science, he is the science laureate at Teaching Channel, an online community for teachers made up of teachers who provide videos to improve teaching practices, share references and create relevant content to keep up with changes in science, technology and engineering. As science and engineering standards are increasing, Tom stays ahead of the game by participating in opportunities that give him first hand experiences that he can bring back to his students.

With not knowing exactly what to expect on a bottom trawl survey, Tom was greatly appreciative of everyone’s openness and eagerness to show and teach him everything. For the most part, he thought the survey would mostly be recording length, weight and sex of the fish. It was a surprise to find out how in depth the sampling was and how much more work needed to be done after the survey ends. Most of the information and samples collected undergo further processing and analysis back at the NEFSC labs while other samples were requested from people working on research projects at outside labs or universities. His excitement to learn was matched by the excitement of the scientific crew to teach. “If you see something, say something.” That is always told to everyone sailing. Either during work-ups or after, everyone was always willing to answer questions and give explanations to any questions.

Tom works with age and growth technician Jillian Price in the ship’s fish processing lab. Data are entered using the touch screen at right for easy retrieval when the cruise is completed. Photo by Christine Kircun, NOAA Fisheries/NEFSC.

Tom compared experiencing this survey to feeling like a 7-year-old and seeing everything for the first time. It’s no picnic living in a marine environment, and to successfully thrive in this mysterious ecosystem, the adaptations marine organisms evolved are “so different and cool!” “The diversity was amazing!”

In particular, he was fascinated with the monkfish. It uses its illicium, a modified dorsal ray, to lore prey to its giant mouth and move it to its stomach using the many sharp teeth in the front and back of the mouth, like a conveyer belt. Another animal that sparked Tom’s interest was the longhorn sculpin with its head covered with many sharp spines and the vibrating hum it makes when agitated. Toward the end of the trip, we started catching lobster, and Tom was excited to hold a lobster whose one claw was the size of his hand!

His students are a clear passion! In-between tows and after shifts, Tom could be found working on his blogs and collecting information and video capturing different phenomena, such as counter shading, eating habits, pressure changes, and defense mechanisms, to name a few. He was constantly brainstorming ideas for interactive lesson plans that explain those phenomena. For example, he mentioned a lesson that would have his students engineer different types of mouths and try to pick up various objects as a way to understand that examining a fish’s mouth is a great way to get an instant idea of their diet.

His students didn’t have to wait for Tom to be back in the classroom to be a part of this journey. He used social media, Facebook, Instagram and Twitter to communicate informally with his 120 following students! As he posted daily pictures and updates, they asked him questions and received a quick reply. And the fun will continue when he returns to his classroom.

After 3 weeks of being away from family and friends, Tom was ready to go back and share everything he learned! And with all his video footage, he’ll have plenty of work to keep him busy for a while.

The Teacher At Sea program is a great way to establish networks and opportunities between Tom, his current and future students, the Teaching Channel community, and the crew and scientists on the ship. It’s always important to encourage and empower a strong scientific community.

Overall, Tom would definitely come back if the opportunity presented itself! “Meeting people who are excited about what they do and who they work with, and learning something new re-energizes me, and makes me want to share the information.”

Note: The NOAA Ship Henry B. Bigelow is currently at sea working along the Northeast U.S. shelf south of New England on the annual Spring Bottom Trawl Survey.

All images and text by Christine Kircun, NOAA/NEFSC

Safety is an issue that everyone on the ship takes very seriously. Fire extinguishers, fire stations, emergency escape breathing devices (EEBDs), immersion suits, defibrillators, and personal flotation devices (PFD) can be found all throughout the ship. Drills are designed by an officer who creates an emergency situation which could be a fire or chemical spill. The emergency is always in a different area, and sometimes if it’s a fire drill, a smoke machine is used which definitely adds an element of reality!

Drills are practiced once a week, and every single person aboard ship has a job during the drill. It could be investigating the emergency, directing communications/activities, or mustering to a safe place, to name a few. Once the alarm for the fire drill is set off, one ten-second tone, everyone immediately stops what they’re doing and heads directly to their assigned muster. The ship crew split into on-scene, damage control (DC) locker forward, DC locker aft, engine room, and bridge groups. The on-scene group is first on the site to assess the emergency. Depending on where, what, and severity of the emergency, people from the DC lockers will assist with any needed equipment or personnel.

Emergency Escape Breathing Devices (EEBDs, orange boxes at left)) and defibrillators (black bag) are part of the ship’s safety equipment.

Meanwhile, the bridge is monitoring the events and guiding the responders. The crew in the engine room have the ability to control the electric grid to either divert electricity from the hazardous area or make sure there is power for some other necessary task.

When the fire is extinguished and area secured, a fire hose is cleaned out by shooting water over the side. This tests the pump and keeps the inside of the hose clean. After the crew remove their gear and clean up the tools, the abandon ship alarm sounds with six short and one long tone. The crew grabs some Emergency Position Indicating Radio Beacons (EPIRBs) and joins the scientific party on the bow. We practice dressing into our immersion suits to make sure it fits, there are no holes, and there’s a light and whistle attached. When everyone is finished, the captain announces “secure from drills and heed all further alarms,” and it’s back to regular ship life.

Members of the science party practice dressing into immersion suits, sometimes called Gumby suits, to make sure it fits, there are no holes, and there’s a light and whistle attached.

Occasionally, we’ll practice a man overboard drill which is announced by three long tones. For this drill, a dummy or some floating object is thrown overboard. The science crew musters to the flying bridge as lookouts. Some crew are stationed at the hospital room and others ride out in a Rigid-Hulled Inflatable Boat (RHIB) to retrieve the “man overboard”. The cold water makes a fast retrieval paramount for the victim’s survival, so it’s best to avoid falling over!

A Rigid-Hulled Inflatable Boat, or RHIB, on the Bigelow is used for science and ship operations, including drills for a “man overboard.”

There is a chemical hood onboard for preserving stomach and gonad samples. Gloves are always worn when filling sample jars, but in case of an accident, there is a spill kit and body/eye wash station nearby.

Chemical hood with safety equipment, including gloves and goggles (left) and the eye wash station (right).

PFDs (personal flotation devices, or life jackets), helmets and man over-board beacons (MOBs) are always worn while working on the back deck. When wet, the MOB sends a signal to the bridge that someone is in the water.

Man overboard beacons (MOBs)

Safety drills aside, we are also encouraged to be mindful of tripping hazards, heavy weather doors, wet stairs, hot electrical boxes, slippery floor surfaces, dryer lint traps and in general, keeping one hand free to help you move around the ship. One rogue wave could easily throw you down a staircase! Ultimately, a successful trip is one where everyone comes back uninjured and alive.

Post and Photos by Christine Kircun, NOAA/NEFSC

The spring survey has officially begun, and I am on night watch with a great team! After a couple of nights to adjust to the sleeping schedule, we’re back in the full swing of sampling.

Not all fish are sampled the same. For some species, such as shortnose greeneye (Chlorophthalmus agassizi), only lengths are taken. For others, such as bluefish (Pomatomus saltatrix), we take length, weight, sex, maturity, stomach contents and otoliths. The bluefish pictured is a 46.5cm (just over 18 inches long) resting (after spawning) female.

A longfin squid and unidentified squid were found in the stomach (image below).

Since the otoliths (pictured below) for bluefish are very fragile, the heads are frozen so the otoliths can be taken out back at the lab.

This is the most common workup. There may also be additional requests from researchers inside and outside the lab for fin clips, gonad samples, muscle samples or whole frozen fish for identification, maturity, and stomach workshops.

For this leg, we’ve had some beautiful weather. On night watch, it’s sometimes easy to forget to go outside, but on those nice days, it’s wonderful to feel the sun and watch the water, hoping to catch a glimpse of a shark, fish, or pod of dolphins.

Though, it’s not always sunny and calm, and we had a little window of unpleasant weather. When the waves and wind are too rough to fish, the main job becomes not

Seas are getting rougher and winds are increasing as another storm approaches.

flying out of your chair when the ship takes a roll, keeping your balance while walking, and trying not to get sick. If you’ve never been sea sick, count yourself lucky because it is miserable. But that’s just another part of life on a ship. Sometimes it’s really tough to be out here, but ultimately, it’s all worth it. There’s a lot of dedicated and excited scientists, volunteers, officers, deckhands and engineers who are all committed to gathering the best data possible, no matter what.